In order to explore the belief that total strain energy accumulation during monotonic tensile fracture is a universal damage parameter, the effect of compressive preloads on specimens failed via tensile loading is analyzed. The motivation behind this analysis is due to the theory of an energy-based life prediction model, which states that the total strain energy required for monotonic tensile fracture is defined as the physical damage quantity for the fatigue lifing model. Two things are observed in order to determine the effects of a compressive preload on tensile monotonic fracture. First, the compressive work is viewed as accumulated damage, thus adding to the total work necessary for failure. Second, tensile works of fractured specimens with and without stored compressive energy are compared to see if the damage parameter is affected. The analysis is conducted through experimental data acquisition from round stock Titanium 6Al-4V dogbone specimens. The results from this study show that compressive damage has a negligible effect on monotonic tensile work to fracture, and combined half-cycle tension and compression preloads have an unnoticeable effect on the tensile work of the final pull to fracture. These results contradict the theory and research validations of the energy-based predictions; however, they provide a platform for future efforts to understand the strain energy correlation between monotonic, low cycle and high cycle failures.

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